This invention relates to the packaging of plastic bags and, in particular, to the packing of T-shirt bags.
Plastic bags of the type known as T-shirt bags are widely used throughout the world. A T-shirt bag is typically formed from a tube of extruded plastic (e.g. polyethylene). The tube is gussetted and seal lines are formed in the gussetted flattened tube to form blanks from which the individual bags are formed. The blanks are cut from the moving tube and bundled, for example, in stacks of 50 to 100 blanks. These blanks are then passed to a cutting station where the handles are die cut to form the individual T-shirt bags. T-shirt bags come in different forms and different sizes and very often include tabs or the like to help mount the bags on a supporting rack. U.S. Pat. Nos. 4,877,473 and 5,464,098 are representative of T-shirt bags.
After manufacture, each bundle is folded in half and placed in a corrugated cardboard box for transportation and storage. FIGS. 1 and 2 show a prior art package in which a bundle of T-shirt bags is placed in a cardboard box 12 shaped to receive the bundle. In FIG. 1, the bundle 10 is folded in half with the open end facing to the left and the folded end to the right. The second folded bundle is placed in the box, as shown in FIG. 2, and positioned so that its open end faces to the right. This is done to compensate for the greater thickness of the bags at the bottom and top seals. Because the bags are folded in halt, the added thickness of the seals causes the bundle to be thicker at its open end as compared to the folded end.
Typically, each box contains 1000 bags, i.e. ten or twenty bundles of one hundred or fifty bags each. Due to the greater thickness of each bundle at its ends, the stack tends to form a depression in the center. The last bundle is usually folded in thirds and placed in the center of the bundle to fill the entire volume of the box.
The handles of the bags are relatively slippery and because of the way in which the bundles are stacked, one on top of the other, the free ends of the handles 10C may tend to shift from their position in the corner of the box during handling and transportation. If this should happen, the stack of bundles becomes unstable and the weight of the bundles needs to be supported by the box. This means that the boxes must be relatively strong which is a factor in the cost of the package as well as transportation.
The invention provides a new way of packaging plastic bags, and in particular, T-shirt bags, in which the stack of bundles is more stable than in the prior art. As a result, the weight bearing capability of the package can be less than in the prior art. This means that the box can be made of thinner, i.e. less expensive, material.
In accordance with the invention, each bundle of bags is folded to form a long and a short portion. Preferably, a third of the bundle is folded over the remaining two thirds so that the long portion is twice as long as the short portion. Each bundle is then placed in the box so that the ends of the bundles in a pair of bundles abut against each other. As a result of this nesting arrangement, the tendency of the bottom or folded part of the bundles to shift during packing, transportation and/or handling is reduced and the stack of bundles at the four corners of the box is more stable. Consequently, the weight bearing capability of the box can be less than before.